/*
 * @(#)MeshInterpolator.java     14/08/02
 * 
 * Author             Rick Wilson
 * Copyright (c) 2014 Rick Wilson
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *     * Neither the name of 'Taareekah' nor the
 *       names of its contributors may be used to endorse or promote products
 *       derived from this software without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT HOLDER> BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */



package util;

//~--- non-JDK imports --------------------------------------------------------

import world.GenericTerrainMap;

import worldgeneration.Util;

/**
 *
 * @author rick
 */
public class MeshInterpolator {

    /**
     *
     * @param generator
     * @param mesh_size
     * @param size
     * @return
     * @throws Exception
     */
    public static GenericTerrainMap perform(InitialValueGenerator generator, int mesh_size, int size) throws Exception {
	int		size_over_mesh_plus_one	= (size / mesh_size) + 1;
	float[][]	temp_buffer		= new float[size_over_mesh_plus_one][size_over_mesh_plus_one];

	for (int x = 0; x < size_over_mesh_plus_one; x++) {
	    for (int y = 0; y < size_over_mesh_plus_one; y++) {
		temp_buffer[x][y]	= generator.getValueAtPoint(x * mesh_size, y * mesh_size, mesh_size, size);
	    }
	}

	GenericTerrainMap	map	= new GenericTerrainMap(size);

	for (int x = 0; x < size; x++) {
	    for (int y = 0; y < size; y++) {
		int	bl_x		= x / mesh_size;
		int	bl_y		= y / mesh_size;
		float	x_float		= (float) x - (float) (bl_x * mesh_size) + 0.5f;
		float	y_float		= (float) y - (float) (bl_y * mesh_size) + 0.5f;
		float[]	corner_values	= { temp_buffer[bl_x][bl_y], temp_buffer[bl_x + 1][bl_y],
					    temp_buffer[bl_x + 1][bl_y + 1], temp_buffer[bl_x][bl_y + 1] };
		float	value	= Util.bilinearInterpolation(corner_values, (float) mesh_size, x_float, y_float);

		map.setValueAtPoint(x, y, value);
	    }
	}

	return map;
    }

    /**
     *
     */
    public static abstract class InitialValueGenerator {

	/**
	 *
	 * @param x
	 * @param y
	 * @param mesh_size
	 * @param size
	 * @return
	 */
	public abstract float getValueAtPoint(int x, int y, int mesh_size, int size);
    }
}


//~ Formatted by Jindent --- http://www.jindent.com
